Of course, it’s always important to test standards-based work amongst the myriad browsers on the market today. A standard can only be a standard if the software supports it. While we’re getting closer, we’re not at the point yet where we can build our code and rely on every browser to get it right without double-checking.
So to that end, there are a few services that we should mention that can help you test. Mac users have it the best, since Microsoft’s Virtual PC allows a Windows session on top of the Mac OS. Windows and Linux users have the option of running VMWare, but thanks to some recent developments, it may not be necessary.
BrowserCam has been at it for a while, and at a reasonable price. It can show you what your site looks like in a huge list of browser on Windows, Mac, and even Linux. iCapture is a new free service, but only covers Safari. KCapture is also free, but only covers Konqueror.
And now that we know better, it is indeed possible to run multiple versions of Internet Explorer on the same Windows install. Ryan Parman has downloads and instructions available going all the way back to MSIE3.